Crane



Dec. 22, 1931.

D. KENDALL ET AL CRANE Filed Aug. 51. 1928 3 Sheets-Sheet .ZZI

INVENTORS aye-m w. 42%

Dec. 22, 1931.

D. KENDALL ET AL CRANE Filed Aug. 31, 1928 3 Sheets-Sheet INVENTORS Dec.22, 1931. D. KENDALL ET AL CRANE 3 Sheets-Sheet Filed Aug. 51, 1928Patented Dec. 22, 1931 UNITED STATES j gi' NT ,rrcai DAVID KEND LL ANDWALTER I). KELLER, or nLLIAiycE, onIo; Assl'errons TO THE AL- LIANCEMACHINE cor/many, or nn-Anon,- OHIO, A coarone'rron or OHIO i cameApplication filed August 31, 1928. Serial I Io'."3()3,192.

character are well known and have been in leg type, such as soaking pitcranes.

Cranes of this type comprise a trolley which carries a stifl leg havingtongs at the lower end thereof. Cranes of this general use for manyyears. We provide a number of improved features contributing toreduction in cost of construction and operation and long life.

Our improved crane is provided with worm gear drives for the severaloperating mechanisms. Worm drives are of special value in a crane ofthis type and permitof a very simple driving connection. The motors arepreferably mounted with their axes extending longitudinally of thetrolley trucks as this insures proper alignment of the parts regardiessof the give of the trolley under load.

The stiff leg is provided with rack teethso that it may be raised orlowered through a gear or pinion engaging such rack teeth, and weprovide a second set of rack teeth disposed opposite those firstmentioned, this second set being connected with a gear which 5 acts asan idler. This prevents slippage of the stiff leg on the idler. Afterthe first set of teeth has worn th'estiff leg may bereversed and thesecond set used for driving.

We mount the operating cage between the wheels of the trolley and soarrange it that it does not project any substantial distance beyond thewheels in the direction of travel of the trolley. In a crane of thistype it is important to reduce to a minimum the distance which the stiffleg is spaced from the end of the crane-way when the trolley has reachedthe limit of its travel along the tracks. By placing the cage as abovedescribed it is possible to bring the stiff leg into very closeproximity with either end of the crane-way.

In. the accompanying drawings illustrating the present preferredembodiment of the invention,

Figure 1 is a side elevation partly broken away of a stiff leg soakingpit crane embodying our improvements, I

Figure 2 is a top plan view,

Figure 3 is a section taken. on the line 111 111 of Figure 1,

' Figure 4 isa vertical section taken on the line IV-T-IV of Figure 3;and

Figure 5 is a'view largely diagrammatic takenat right anglesto the viewof Figured and showing the stiff leg. i y

.In general',the crane shownin the drawings embodies many of. thefeatures of the crane shown inthe patent. to 'Milo'Shutt, 1,487,032,dated March 18th, 1924. It cont prises atrolleymade of spaced trucks'Qconnected by structural members 3, and each prorvidedwith-trackuwheelsl and 5adapted torun on'spaced tracks T on thecrane bridge. The wheels 4 are i dler wheels and the wheels 5 aredriving Wheels- Each wheel 5 is provided witha'gear 6 meshing with apinion 7 on a shaft 8. Theishaft 8 is driven through i gearing 9 from atrolleymotor 10. H i The operating cage .11, as best shown in Figure 3,,lies between the trucks 2 and does not extend any substantial distancebeyond the-track wheeled. This materially reduces the amoun't of spaceateither end of the run} way which'cannot be reached by the stiff leg.The stiff leg comprises a hollow casting 12 having rackteeth 13 formedon diametrically opposite sides. The'stiif leg is symmetrical about ahorizontal center line, as viewed in Figure 3, so that it may be takenout, turned through 1809-and replaced. The stiff leg is.

raised and lowered by a pinion 1&1 onja shaft 15. Thezshaft 15- carriesa loose sleeve 16 on whicha worm gear 17 is mounted, The worm gearmesheswith a worm wheeli 18'on thel'shaft of a motor 19. As best seenfrom Figure 3, the axis of the motor 19 extends longitudinally of thetruck 2 upon which it isumounted. One end of thesleeve 16 is toothed.and engages a correspondingly toothed sleeve QOinfthe shaft 15. Theshaft makes spline connectionv with the sleeve 20 and the teeth of thesleeve 20 areforced into engagament with the teeth of the sleeve 16 byacompression spring 21,- The mechanisin thus above described constitutesa slip 5 connection so that if the operator fails to shut I off themotor 19 when the stiff leg is lowered into engagement, with theingot tohe lifted,

continued rotation of the motorwill not cause thet'rolleylto climb 'upthe stiff leg no slippingcan take place between the two N Thiseliminates any wearing of flat spots and consequent looseness in thestiff leg. i

. The tongs 24; at thebottom of the stiff leg carry a gear 25 ine'shin'with a pinion- 26 on a square shaft27fexten ing longitudinally of the anleg. The shaft slides threuh a bevel gear 28 carried by the trolley andconnected through a 'corresponding bevel gear to a "shaft '29. The shaft29 is connected through worm gearingindi cated at 30 to a tongs'rotatingmotor 31.7 .The tongs rotatdirection operable upon attempted unduelowering of'the stiff leg. 7

2. A crane comprising a vertically movable stifi leg, a rackthereon, areversible motor, gearing connecting the motor with the rack whereby thestiff leg may be driven upwardly or downwardly, and a slip mechanisminterposed in the gearing, said slip mechanism comprising cooperatingrotatable members havind inter-engaging teeth, the teeth having axiallyextending faces and inelined faces, and means yieldingly' urging therotatablemembers together, said slip' mechanism rovidin a positivedrivin con v 25 a b nection in one direction and a slippingconnest-ionin the other direction operable upon attempted undue lowering of thestiff leg.

In testimony whereof we' have hereunto set oiir hands. r

, DAVID KENDALL.

WALTER D. KELLER.

in'g motor is also mounted on one of the e ru'cks 2 and its axis extendslongitudinally thereof.

The tongs opening and closing mechav n'ism is best shown in Figures 1and 4. It comprises. le've'r arms 32 pivoted at '33 to the 1towerstructure 34"of thetroll'ey The levers 32c2'1'rr; she-ave wheeis3'5 and tongs "operating cab es 36 (se'eFigure 1) pass over thesesheaves and "areconne'cte'd to an equ'aliz'er bar. ion the tongs"cl'osingrod 38. cables 36 extend from the'sheaves around sheaves 39rotatable on the pivot shaft thence downwardly 1 around; sheave wheels40 on a muster weight 41, and tnence upward- 1y to be dea'fc'he' n'dedat 42. The counter weight 'isconnec'ted through cables 13 runlene oversheave Wheels 44 to the. stifi leg.

The I levers 32, are connected through a heavy counter b'a'lancin ii'nir45 ma crank 'p'i'nj46 'onhcranky. The crank 47 is-connecte'd throughworm gearing 48 the tongs opening andel'osing motor49.- We haveillustrated andd'escribed the present preferredform ofour invention, itis not limited to 't'his form alone, as it maybe The embodied withinthescope of "the" following i claimsq Y e V Weehnn: v I H 1. A cranecomprising a: stiff le'g"having a ra ekro'rmed thereon, a motor, apinion engaging "the rack, gearing connecting the motor and the pinion,said gearing including a worm gear, and aslip mechanism-interposed V inthe 'eari'ngsaid slip mechanism comprising'c'ooperating rotatablemembershaving inte ngagi'n g teeth, "the teeth having axially ex tending face's"and "inclined faces, and V means y'ielding l'y urgingthe rotatable mem-'be'is together, said slip mechanism providing a positive driving"connection in one direction and a slipping'connetion in'theother

